Effect of Intrav it real Ceftazidime Injection in Experimental Pseudomonas Endophthalmitis

Lee, W J; Lee, J H; Kim, J S

Abstract

Aminoglycosides have been used in Gram negative bacterial endoph-thalmitis as mainstay of treatment but may have potential retinal toxicity when injected intravitreally. This investigation was conducted to evaluate the efficacy and appropriate timing of intravitreal ceftazidime as the substitute drug for aminoglyco-sides. 20 white rabbits were grouped into three; 4 in the control group, each in Group I and II. Unilateral vitrectomy was performed in all 20 rabbits, 2 weeks before the experiment. After postoperative inflammation had quieted down, Pseudomonas aeruginosa strain was inoculated in all 40 eyes. Ceftazidime (2.25mg/0.1ml) was injected intravitreally after 24 hours in Group I and 48 hours in Group II, respectively and ceftazidime injection was not performed in the control group. Vitreous aspirate culture and histologic examination were performed 24 and 48 hours after ceftazidime injection in each group and the results were compared. On vitreous aspirate culture, no growth has been noted in Group I, irrelevant to vitrectomy. In Group II and the control group, Pseudomonas aeru-ginosa have grown; the shorter the period of intravitreal bacterial inoculation and the longer the duration of contact with the antibiotics, the lesser number of bacterial growth has been noted. The severity of histopathologic findings showed the same tendency. In conclusion, ceftazidime seems to be an effective substitute drug for aminoglycosides in Pseudomonas aeruginosa endophthalmitis.